Fuel cell and use of iron-based alloys for the construction of fuel cells

Abstract

A fuel cell is provided which includes iron-based alloys for the construction of the solid parts of the fuel cell. The fuel cell includes a membrane electrode unit and solid constructive parts which may include current collectors, a cell frame and a bipolar plate. At least one of these solid constructive parts is made from an iron-based material that preferably has an effective weight percent of iron of greater than or equal to 26.9 percent.

What is claimed is:  
     
       1. A fuel cell comprising a membrane electrode unit and a plurality of solid constructive parts selected from a group consisting of a plurality of current collectors, a cell frame, and a bipolar plate, at least one of the solid constructive parts comprising a Fe-based material comprising the following composition: 
       Cr content: 8.25-46.5 weight %  
       Mo content: 1.25-14.0 weight %  
       Ni content: 2.25-40.5 weight %  
       N content: 0.02-1 weight %  
       Fe content: remainder to 100 weight %,  
       wherein the Fe-based material comprises an effective sum greater than or equal to 26.9, and effective sum is defined as Pitting Resistance Equivalent (PRE).  
     
     
       2. The fuel cell of claim  1 , wherein the Fe-based material further comprises the following composition: 
       Cr content: 16.5-25.0 weight %  
       Mo continent: 2.5-7.0 weight %  
       Ni content: 4.5-26.0 weight %  
       N content: 0.04-0.5 weight %  
       Fe content: remainder to 100 weight %.  
     
     
       3. The fuel cell of claim  1 , wherein the Fe based material further comprises the following composition: 
       C content: 0.-0.03 weight %  
       Si content: 0-1 weight %  
       Cu content: 0-2.0 weight %  
       Mn content: 0-6.5 weight %  
       Nb content: 0-0.25 weight %  
       P content: 0-0.045 weight %  
       S content 0-0.03 weight %  
       Fe content: remainder to 100 weight %.  
     
     
       4. The fuel cell of claim  1 , wherein the Fe-based material is surface treated. 
     
     
       5. The fuel cell of claim  1 , wherein the fuel cell is a PEM fuel cell. 
     
     
       6. A method of constructing a fuel cell comprising solid constructive parts, the method comprising the step of fabricating the solid constructive parts from an Fe-based alloy comprising the composition: 
       Cr content: 8.25-46.5 weight %  
       Mo content: 1.25-14.0 weight %  
       Ni content: 2.25-40.5 weight %  
       N content: 0.02-1 weight %  
       Fe content: remainder to 100 weight %,  
       wherein the Fe-based material comprises an effective sum greater than or equal to 26.9, and effective sum is defined as Pitting Resistance Equivalent (PRE).  
     
     
       7. The method of claim  6 , wherein the Fe-based material further comprises the following composition: 
       Cr content: 16.5-25.0 weight %  
       Mo content: 2.5-7.0 weight %  
       Ni content: 4.5-26.0 weight %  
       N content: 0.04-0.5 weight %  
       Fe content: remainder to 100 weight %.  
     
     
       8. The method of claim  6 , wherein the Fe-based material further comprises the following composition: 
       C content: 0-0.03 weight %  
       Si content: 0-1 weight %  
       Cu content: 0-2.0 weight %  
       Mn content: 0-6.5 weight %  
       Nb content: 0-0.25 weight %  
       P content: 0-0.045 weight %  
       S content: 0-0.03 weight %  
       Fe content: remainder to 100 weight %.  
     
     
       9. The method of claim  6 , wherein the Fe based material is surface treated. 
     
     
       10. The method of claim  6 , wherein the fuel cell is a PEM fuel cell.